The study of the oral manifestations of human immunodeficiency virus (HIV) infection offers unique and important opportunities to improve our knowledge of the epidemiology of AIDS and HIV. During the last five years, the Oral AIDS Center has developed a good understanding for certain risk groups (such as homosexual men) as to which oral lesions are associated with HIV infection, and their prognostic significance for the development of AIDS. During the next five years, we will answer these questions for other, less well studied populations such as women and racial/ethnic minorities. Building on our findings from the first five years, we will now more precisely determine where oral lesions fit in the overall pattern of progression from HIV infection to AIDS by evaluating three major areas: (1). The relationship between oral lesions and HIV infection (including time from infection to lesion), and the association between oral lesions and degree of immune suppression, as reflected in CD4+ count; (2). The prognostic significance of oral lesions for the development of AIDS, and for survival; (3). Whether certain factors (including sexual practices, drug use practices, and medical therapies such as zidovudine) increase or decrease the likelihood of developing specific lesions. We will also collaborate on clinical and molecular studies with the Clinical core and (through the Core) with Projects 2 and 3. The cohort studies will continue to be our primary source of data for these investigations, although we will also continue our collaboration with UCSF Stomatology Clinical Center/Oral AIDS Clinic and the UCSF Adult Immunodeficiency Clinic. The past five years have produced excellent descriptive and analytic studies concerning the oral manifestations of HIV. Our current and future research based on this knowledge will allow us to better define, for different populations, the relationship of oral lesions to the entire spectrum of HIV disease progression.